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<FONT color="green">001</FONT>    /*<a name="line.1"></a>
<FONT color="green">002</FONT>     * Licensed to the Apache Software Foundation (ASF) under one or more<a name="line.2"></a>
<FONT color="green">003</FONT>     * contributor license agreements.  See the NOTICE file distributed with<a name="line.3"></a>
<FONT color="green">004</FONT>     * this work for additional information regarding copyright ownership.<a name="line.4"></a>
<FONT color="green">005</FONT>     * The ASF licenses this file to You under the Apache License, Version 2.0<a name="line.5"></a>
<FONT color="green">006</FONT>     * (the "License"); you may not use this file except in compliance with<a name="line.6"></a>
<FONT color="green">007</FONT>     * the License.  You may obtain a copy of the License at<a name="line.7"></a>
<FONT color="green">008</FONT>     *<a name="line.8"></a>
<FONT color="green">009</FONT>     *     http://www.apache.org/licenses/LICENSE-2.0<a name="line.9"></a>
<FONT color="green">010</FONT>     *<a name="line.10"></a>
<FONT color="green">011</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.11"></a>
<FONT color="green">012</FONT>     * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.12"></a>
<FONT color="green">013</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.13"></a>
<FONT color="green">014</FONT>     * See the License for the specific language governing permissions and<a name="line.14"></a>
<FONT color="green">015</FONT>     * limitations under the License.<a name="line.15"></a>
<FONT color="green">016</FONT>     */<a name="line.16"></a>
<FONT color="green">017</FONT>    package org.apache.commons.configuration.tree;<a name="line.17"></a>
<FONT color="green">018</FONT>    <a name="line.18"></a>
<FONT color="green">019</FONT>    import java.util.ArrayList;<a name="line.19"></a>
<FONT color="green">020</FONT>    import java.util.Iterator;<a name="line.20"></a>
<FONT color="green">021</FONT>    import java.util.LinkedList;<a name="line.21"></a>
<FONT color="green">022</FONT>    import java.util.List;<a name="line.22"></a>
<FONT color="green">023</FONT>    <a name="line.23"></a>
<FONT color="green">024</FONT>    /**<a name="line.24"></a>
<FONT color="green">025</FONT>     * &lt;p&gt;<a name="line.25"></a>
<FONT color="green">026</FONT>     * A specialized implementation of the {@code NodeCombiner} interface<a name="line.26"></a>
<FONT color="green">027</FONT>     * that performs a merge from two passed in node hierarchies.<a name="line.27"></a>
<FONT color="green">028</FONT>     * &lt;/p&gt;<a name="line.28"></a>
<FONT color="green">029</FONT>     * &lt;p&gt;<a name="line.29"></a>
<FONT color="green">030</FONT>     * This combiner performs the merge using a few rules:<a name="line.30"></a>
<FONT color="green">031</FONT>     * &lt;ol&gt;<a name="line.31"></a>
<FONT color="green">032</FONT>     * &lt;li&gt;Nodes can be merged when attributes that appear in both have the same value.&lt;/li&gt;<a name="line.32"></a>
<FONT color="green">033</FONT>     * &lt;li&gt;Only a single node in the second file is considered a match to the node in the first file.&lt;/li&gt;<a name="line.33"></a>
<FONT color="green">034</FONT>     * &lt;li&gt;Attributes in nodes that match are merged.<a name="line.34"></a>
<FONT color="green">035</FONT>     * &lt;li&gt;Nodes in both files that do not match are added to the result.&lt;/li&gt;<a name="line.35"></a>
<FONT color="green">036</FONT>     * &lt;/ol&gt;<a name="line.36"></a>
<FONT color="green">037</FONT>     * &lt;/p&gt;<a name="line.37"></a>
<FONT color="green">038</FONT>     *<a name="line.38"></a>
<FONT color="green">039</FONT>     * @author &lt;a<a name="line.39"></a>
<FONT color="green">040</FONT>     * href="http://commons.apache.org/configuration/team-list.html"&gt;Commons<a name="line.40"></a>
<FONT color="green">041</FONT>     * Configuration team&lt;/a&gt;<a name="line.41"></a>
<FONT color="green">042</FONT>     * @version $Id: MergeCombiner.java 1301991 2012-03-17 20:18:02Z sebb $<a name="line.42"></a>
<FONT color="green">043</FONT>     * @since 1.7<a name="line.43"></a>
<FONT color="green">044</FONT>     */<a name="line.44"></a>
<FONT color="green">045</FONT>    public class MergeCombiner extends NodeCombiner<a name="line.45"></a>
<FONT color="green">046</FONT>    {<a name="line.46"></a>
<FONT color="green">047</FONT>        /**<a name="line.47"></a>
<FONT color="green">048</FONT>         * Combines the given nodes to a new union node.<a name="line.48"></a>
<FONT color="green">049</FONT>         *<a name="line.49"></a>
<FONT color="green">050</FONT>         * @param node1 the first source node<a name="line.50"></a>
<FONT color="green">051</FONT>         * @param node2 the second source node<a name="line.51"></a>
<FONT color="green">052</FONT>         * @return the union node<a name="line.52"></a>
<FONT color="green">053</FONT>         */<a name="line.53"></a>
<FONT color="green">054</FONT>    <a name="line.54"></a>
<FONT color="green">055</FONT>        @Override<a name="line.55"></a>
<FONT color="green">056</FONT>        public ConfigurationNode combine(ConfigurationNode node1, ConfigurationNode node2)<a name="line.56"></a>
<FONT color="green">057</FONT>        {<a name="line.57"></a>
<FONT color="green">058</FONT>            ViewNode result = createViewNode();<a name="line.58"></a>
<FONT color="green">059</FONT>            result.setName(node1.getName());<a name="line.59"></a>
<FONT color="green">060</FONT>            result.setValue(node1.getValue());<a name="line.60"></a>
<FONT color="green">061</FONT>            addAttributes(result, node1, node2);<a name="line.61"></a>
<FONT color="green">062</FONT>    <a name="line.62"></a>
<FONT color="green">063</FONT>            // Check if nodes can be combined<a name="line.63"></a>
<FONT color="green">064</FONT>            List&lt;ConfigurationNode&gt; children2 = new LinkedList&lt;ConfigurationNode&gt;(node2.getChildren());<a name="line.64"></a>
<FONT color="green">065</FONT>            for (ConfigurationNode child1 : node1.getChildren())<a name="line.65"></a>
<FONT color="green">066</FONT>            {<a name="line.66"></a>
<FONT color="green">067</FONT>                ConfigurationNode child2 = canCombine(node1, node2, child1, children2);<a name="line.67"></a>
<FONT color="green">068</FONT>                if (child2 != null)<a name="line.68"></a>
<FONT color="green">069</FONT>                {<a name="line.69"></a>
<FONT color="green">070</FONT>                    result.addChild(combine(child1, child2));<a name="line.70"></a>
<FONT color="green">071</FONT>                    children2.remove(child2);<a name="line.71"></a>
<FONT color="green">072</FONT>                }<a name="line.72"></a>
<FONT color="green">073</FONT>                else<a name="line.73"></a>
<FONT color="green">074</FONT>                {<a name="line.74"></a>
<FONT color="green">075</FONT>                    result.addChild(child1);<a name="line.75"></a>
<FONT color="green">076</FONT>                }<a name="line.76"></a>
<FONT color="green">077</FONT>            }<a name="line.77"></a>
<FONT color="green">078</FONT>    <a name="line.78"></a>
<FONT color="green">079</FONT>            // Add remaining children of node 2<a name="line.79"></a>
<FONT color="green">080</FONT>            for (ConfigurationNode c : children2)<a name="line.80"></a>
<FONT color="green">081</FONT>            {<a name="line.81"></a>
<FONT color="green">082</FONT>                result.addChild(c);<a name="line.82"></a>
<FONT color="green">083</FONT>            }<a name="line.83"></a>
<FONT color="green">084</FONT>            return result;<a name="line.84"></a>
<FONT color="green">085</FONT>        }<a name="line.85"></a>
<FONT color="green">086</FONT>    <a name="line.86"></a>
<FONT color="green">087</FONT>        /**<a name="line.87"></a>
<FONT color="green">088</FONT>         * Handles the attributes during a combination process. First all attributes<a name="line.88"></a>
<FONT color="green">089</FONT>         * of the first node will be added to the result. Then all attributes of the<a name="line.89"></a>
<FONT color="green">090</FONT>         * second node, which are not contained in the first node, will also be<a name="line.90"></a>
<FONT color="green">091</FONT>         * added.<a name="line.91"></a>
<FONT color="green">092</FONT>         *<a name="line.92"></a>
<FONT color="green">093</FONT>         * @param result the resulting node<a name="line.93"></a>
<FONT color="green">094</FONT>         * @param node1 the first node<a name="line.94"></a>
<FONT color="green">095</FONT>         * @param node2 the second node<a name="line.95"></a>
<FONT color="green">096</FONT>         */<a name="line.96"></a>
<FONT color="green">097</FONT>        protected void addAttributes(ViewNode result, ConfigurationNode node1,<a name="line.97"></a>
<FONT color="green">098</FONT>                ConfigurationNode node2)<a name="line.98"></a>
<FONT color="green">099</FONT>        {<a name="line.99"></a>
<FONT color="green">100</FONT>            result.appendAttributes(node1);<a name="line.100"></a>
<FONT color="green">101</FONT>            for (ConfigurationNode attr : node2.getAttributes())<a name="line.101"></a>
<FONT color="green">102</FONT>            {<a name="line.102"></a>
<FONT color="green">103</FONT>                if (node1.getAttributeCount(attr.getName()) == 0)<a name="line.103"></a>
<FONT color="green">104</FONT>                {<a name="line.104"></a>
<FONT color="green">105</FONT>                    result.addAttribute(attr);<a name="line.105"></a>
<FONT color="green">106</FONT>                }<a name="line.106"></a>
<FONT color="green">107</FONT>            }<a name="line.107"></a>
<FONT color="green">108</FONT>        }<a name="line.108"></a>
<FONT color="green">109</FONT>    <a name="line.109"></a>
<FONT color="green">110</FONT>        /**<a name="line.110"></a>
<FONT color="green">111</FONT>         * Tests if the first node can be combined with the second node. A node can<a name="line.111"></a>
<FONT color="green">112</FONT>         * only be combined if its attributes are all present in the second node and<a name="line.112"></a>
<FONT color="green">113</FONT>         * they all have the same value.<a name="line.113"></a>
<FONT color="green">114</FONT>         *<a name="line.114"></a>
<FONT color="green">115</FONT>         * @param node1 the first node<a name="line.115"></a>
<FONT color="green">116</FONT>         * @param node2 the second node<a name="line.116"></a>
<FONT color="green">117</FONT>         * @param child the child node (of the first node)<a name="line.117"></a>
<FONT color="green">118</FONT>         * @return a child of the second node, with which a combination is possible<a name="line.118"></a>
<FONT color="green">119</FONT>         */<a name="line.119"></a>
<FONT color="green">120</FONT>        protected ConfigurationNode canCombine(ConfigurationNode node1,<a name="line.120"></a>
<FONT color="green">121</FONT>                ConfigurationNode node2, ConfigurationNode child, List&lt;ConfigurationNode&gt; children2)<a name="line.121"></a>
<FONT color="green">122</FONT>        {<a name="line.122"></a>
<FONT color="green">123</FONT>            List&lt;ConfigurationNode&gt; attrs1 = child.getAttributes();<a name="line.123"></a>
<FONT color="green">124</FONT>            List&lt;ConfigurationNode&gt; nodes = new ArrayList&lt;ConfigurationNode&gt;();<a name="line.124"></a>
<FONT color="green">125</FONT>    <a name="line.125"></a>
<FONT color="green">126</FONT>            List&lt;ConfigurationNode&gt; children = node2.getChildren(child.getName());<a name="line.126"></a>
<FONT color="green">127</FONT>            Iterator&lt;ConfigurationNode&gt; it = children.iterator();<a name="line.127"></a>
<FONT color="green">128</FONT>            while (it.hasNext())<a name="line.128"></a>
<FONT color="green">129</FONT>            {<a name="line.129"></a>
<FONT color="green">130</FONT>                ConfigurationNode node = it.next();<a name="line.130"></a>
<FONT color="green">131</FONT>                Iterator&lt;ConfigurationNode&gt; iter = attrs1.iterator();<a name="line.131"></a>
<FONT color="green">132</FONT>                while (iter.hasNext())<a name="line.132"></a>
<FONT color="green">133</FONT>                {<a name="line.133"></a>
<FONT color="green">134</FONT>                    ConfigurationNode attr1 = iter.next();<a name="line.134"></a>
<FONT color="green">135</FONT>                    List&lt;ConfigurationNode&gt; list2 = node.getAttributes(attr1.getName());<a name="line.135"></a>
<FONT color="green">136</FONT>                    if (list2.size() == 1<a name="line.136"></a>
<FONT color="green">137</FONT>                        &amp;&amp; !attr1.getValue().equals(list2.get(0).getValue()))<a name="line.137"></a>
<FONT color="green">138</FONT>                    {<a name="line.138"></a>
<FONT color="green">139</FONT>                        node = null;<a name="line.139"></a>
<FONT color="green">140</FONT>                        break;<a name="line.140"></a>
<FONT color="green">141</FONT>                    }<a name="line.141"></a>
<FONT color="green">142</FONT>                }<a name="line.142"></a>
<FONT color="green">143</FONT>                if (node != null)<a name="line.143"></a>
<FONT color="green">144</FONT>                {<a name="line.144"></a>
<FONT color="green">145</FONT>                    nodes.add(node);<a name="line.145"></a>
<FONT color="green">146</FONT>                }<a name="line.146"></a>
<FONT color="green">147</FONT>            }<a name="line.147"></a>
<FONT color="green">148</FONT>    <a name="line.148"></a>
<FONT color="green">149</FONT>            if (nodes.size() == 1)<a name="line.149"></a>
<FONT color="green">150</FONT>            {<a name="line.150"></a>
<FONT color="green">151</FONT>                return nodes.get(0);<a name="line.151"></a>
<FONT color="green">152</FONT>            }<a name="line.152"></a>
<FONT color="green">153</FONT>            if (nodes.size() &gt; 1 &amp;&amp; !isListNode(child))<a name="line.153"></a>
<FONT color="green">154</FONT>            {<a name="line.154"></a>
<FONT color="green">155</FONT>                Iterator&lt;ConfigurationNode&gt; iter = nodes.iterator();<a name="line.155"></a>
<FONT color="green">156</FONT>                while (iter.hasNext())<a name="line.156"></a>
<FONT color="green">157</FONT>                {<a name="line.157"></a>
<FONT color="green">158</FONT>                    children2.remove(iter.next());<a name="line.158"></a>
<FONT color="green">159</FONT>                }<a name="line.159"></a>
<FONT color="green">160</FONT>            }<a name="line.160"></a>
<FONT color="green">161</FONT>    <a name="line.161"></a>
<FONT color="green">162</FONT>            return null;<a name="line.162"></a>
<FONT color="green">163</FONT>        }<a name="line.163"></a>
<FONT color="green">164</FONT>    }<a name="line.164"></a>




























































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